What Does Herd Immunity Mean?

With the prospects of being immunized for Covid-19 increasing as the doses become more available, the news is reporting how we need higher numbers of vaccinated people to achieve herd immunity.  NPR has a great graphic using fictitious viral scenarios that can be set in motion to help you understand exactly why herd immunity is a very good thing.  (They don’t use Covid-19 specifically because there are too many unknowns, but it is applicable data.)  The bottom line:  the faster we have everyone protected by a vaccine, the better.  Learn the details here: